Using the Internet of Things to Teach Good Software Engineering Practice to High School Students

This paper describes a course to introduce high school students to software engineering in practice using the Internet Of Things (IoT). IoT devices allow students to get quick, visible results without watering down technical aspects of programming and networking. The course has three broad goals: (1) to make software engineering fun and applicable, with the aim of recruiting traditionally underrepresented groups into computing; (2) to make young students begin to approach problems with a design mindset; and (3) to show students that computer science, generally, and software engineering, specifically, is about much more than programming. The course unfolds in three segments. The first is a whirlwind introduction to a subset of IoT technologies. Students complete a specific task (or set of tasks) using each technology. This segment culminates in a “do-it-yourself” project, in which the students implement a simple IoT application using their basic knowledge of the technologies. The course’s second segment introduces software engineering practices, again primarily via hands-on practical tutorials. In the third segment of the course, the students conceive of, design, and implement a project that uses the technologies introduced in the first segment, all while being attentive to the good software engineering practices acquired in the second segment. In addition to presenting the course curriculum, the paper also discusses a first offering of the course in a threeweek summer intensive program in 2017, including assessments done to evaluate the curriculum.Cockrell School of Engineerin

Absolute evaporation rates of non-rotating neutral PAH clusters

Clusters of polycyclic aromatic hydrocarbons (PAHs) have been proposed as candidates for evaporating very small grains, which are thought to be precursors of free-flying PAHs. Evaporation rates have been calculated so far only for species containing up to a few 100 C atoms, whereas interstellar PAH clusters could contain up to ~1000 C atoms. We present a method that generalises the calculation of the statistical evaporation rate of large PAH clusters and provides rates for species containing up to ~1000 C-atoms. The evaporation of non-rotating neutral homo-molecular PAH clusters containing up to 12 molecules from a family of highly symmetric compact PAHs is studied. Statistical calculations were performed and completed with molecular dynamics simulations at high internal energies to provide absolute values for the evaporation rate and distributions of kinetic energy released. The calculations used explicit atom-atom Lennard-Jones potentials in the rigid molecule approximation. A new method is proposed to take both inter- and intra-molecular vibrations into account. Without any parameter adjustment, the calculated evaporation rates agree well with available experimental data. We find that the non-rotation assumption has a limited impact on the evaporation rates. The photostability of PAH clusters increases dramatically with the size of molecules in the clusters, and to a lesser extent with the number of molecules in the clusters. For values of the UV radiation field that are typical of the regions where evaporating very small grains are observed, the smallest clusters in this study (~50 C-atoms) are found to be quickly photo-evaporated, whereas the largest clusters (~1000 C-atoms) are photostable. Our results support the idea that large PAH clusters are good candidates for evaporating very small grains.Comment: 13 pages, 10 figure

MADServer: An Architecture for Opportunistic Mobile Advanced Delivery

Rapid increases in cellular data traffic demand creative alternative delivery vectors for data. Despite the conceptual attractiveness of mobile data offloading, no concrete web server architectures integrate intelligent offloading in a production-ready and easily deployable manner without relying on vast infrastructural changes to carriers’ networks. Delay-tolerant networking technology offers the means to do just this. We introduce MADServer, a novel DTN-based architecture for mobile data offloading that splits web con- tent among multiple independent delivery vectors based on user and data context. It enables intelligent data offload- ing, caching, and querying solutions which can be incorporated in a manner that still satisfies user expectations for timely delivery. At the same time, it allows for users who have poor or expensive connections to the cellular network to leverage multi-hop opportunistic routing to send and receive data. We also present a preliminary implementation of MADServer and provide real-world performance evaluations

Live yeast as a possible modulator of polyunsaturated fatty acid biohydrogenation in the rumen

In dairy cows, several studies focused on the effects of sodium bicarbonate and fibre on ruminal linoleic acid (c9c12-C18:2) biohydrogenation (BH) whereas literature is scarce about the effect of live yeast, used as a feed additive. The objective of this in vivo study was to evaluate the capacity of two dietary feed additives, sodium bicarbonate and live yeast (Strain Sc47), and hay to modulate ruminal BH and particularly conjugated linoleic acids (CLA) and trans-monoenoic acids (t-C18:1) production. Four dry dairy cows fitted with ruminal cannula, were used in a 4×4 Latin square design. They were given a control diet (CD) at a daily feeding rate of 10.4 kg of dry matter/cow supplemented with 100 g/d of sodium bicarbonate or 5 g/d of live yeast or a hay diet formulated to provide the same main fatty acids (FA) as CD during a 14-d experimental period. Ruminal pH and redox potential were measured from 1 h before feeding to 8 h after, and ruminal fluid samples were taken at 5 h after feeding for volatile fatty acids, ammonia and fatty acid determination. In addition to the in vivo experiment, an in vitro experiment was carried out to ascertain the possible mode of action of live yeast on c9c12-C18:2 BH: ruminal fluid was obtained from a donor cow fed with hay and was incubated in batch cultures over 6 h with a 6-pH buffer using starch, urea and grape seed oil as substrates. Results gathered from both experiments suggested that live yeast supplement increased the accumulation of t-C18:1 compared to sodium bicarbonate and prevented the formation of C18:0 which is usually observed when hay is added to a high concentrate diet. The accumulation of t-C18:1 observed in presence of live yeast was probably due to an inhibition of the second reduction step as a result of a more complete isomerisation of c9c12-C18:2

Effect of live yeast on ruminal biohydrogenation. A preliminary in vitro approach

Introduction : Ruminant dietary feed additives such as live yeasts are used on field because of their ability to induce a better diet utilisation. Even if studies on their mode of action are still going on, references are scarce about live yeast diet supplementation and ruminal biohydrogenation (BH) of dietary lipids in dairy cows. During the ruminal BH, some interesting fatty acids (FA), like conjugated linoleic acids (CLA), are synthesised by bacteria, and then could be transferred to milk. This experiment studied live yeast influence on ruminal BH with an in vitro approach. Materials and methods: Ruminal fluid was sucked out from a rumen fistulated dry dairy cow receiving a hay-based diet (57% hay, 43% concentrates) and divided in 10 flasks containing substrates (starch, hay and urea) and a buffer solution (pH 7). In 5 flasks, live Saccharomyces cerevisiae (1010 CFU/g DM, BIOSAF Sc 47, Lesaffre Feed Additives, France) was dosed at 0.15g per flask. All flasks were incubated kept from light and air in a waterbath rotary shaker at 39°C. Two not incubated control flasks without added fat were realized to determine the initial FA amount. After 6h, the incubated flasks were placed into iced water to stop microbial activity and the content was lyophilized for FA extraction and quantification by gas chromatography. Rates and efficiencies of the three reactions composing BH of C18:2 were calculated1. Data were submitted to an analysis of variance. Results and Discussion : Rates and efficiencies of the 3 steps of BH were not significantly modified by live yeast. Composition of FA of control and treated flaks did not strongly differ. The percentage C16:1+C17:0anteiso was twice higher (P0.05), including C18:2 BH intermediates, like trans-11 or trans-10 isomers of CLA and trans-C18:1. Live yeast had no effect in such conditions on the extent of C18:2 (P=0.566) or C18:3 BH (P=0.838), 51% and 54% on average disappeared during incubation, respectively. Conclusion : The fermentative substrate containing hay and the pH were favorable to a high ruminal BH. Live yeast had no effect in such conditions but this work showed that yeast had no adverse effect on BH. Because of live yeast supplementation being advised in case of high concentrate diets inducing ruminal acidosis, further studies will be carried out to investigate live yeast effect on BH in such conditions

La réforme comme opportunité professionnelle ?:Autonomie des établissements et montée en puissance des cadres administratifs des universités

Cet article analyse le rôle joué par les cadres administratifs des universités françaises dans la mise en œuvre de la loi Libertés et responsabilités des universités de 2007. Il vise à combler un point aveugle de la littérature sur les transformations des bureaucraties professionnelles, qui a largement négligé l’analyse des fonctions de support administratif, alors même que celles-ci peuvent être l’un des vecteurs privilégiés de logiques managériales. Porteurs d’un « esprit de mission » gestionnaire, une partie de ces cadres saisissent l’opportunité de la réforme pour rationaliser l’administration des établissements et consolider leurs propres capacités d’action. Toutefois, loin de remettre en cause l’autorité des dirigeants universitaires, ils cherchent à se légitimer en développant des registres d’intervention distincts et en œuvrant au renforcement du pouvoir de ces derniers.Institutional autonomy and the rise of administrators in French universities Following an extensive reform of university governance in 2007, this article analyzes the changing role of professional administrators in French universities, such as heads of administrative services, functional experts and support staff managers. Drawing on two case studies, it addresses a blind spot in the literature on public sector professional bureaucracies, which has largely overlooked the role that support staff may play in the development of managerialism in public institutions. The reform provided space allowing these actors to promote the rationalization and the centralization of university administrations. While this process vastly increased their influence over organizational sub-units within universities, they have been cautious not to challenge the authority and role of academic leaders in university governance. In order to legitimize their action, they have positioned themselves as management experts serving the goals of academic leaders by tightening budgetary control and providing resources at the disposal of university presidencies

Active Coordination in Ad Hoc Networks

The increasing ubiquity of communicating mobile devices and vastly different mobile application needs have led to the emergence of middleware models for ad hoc networks that simplify application programming. One such system, EgoSpaces, addresses specific needs of individual applications, allowing them to define what data is included in their operating context using declarative specifications constraining properties of data, agents that own the data, hosts on which those agents are running, and attributes of the ad hoc network. In the resulting coordination model, application agents interact with a dynamically changing environment through a set of views, or custom defined projections of the set of data present in the surrounding ad hoc network. This paper builds on EgoSpaces by allowing agents to assign behaviors to their personal-ized views. Behaviors consist of actions that are automatically performed in response to specified changes in a view. Behaviors discussed in this paper encompass reactive programming, transparent data migration, automatic data duplication, and event capture. Formal semantic definitions and programming examples are given for each behavior

A Protocol for Supporting Context Provision in Wireless Mobile Ad Hoc Networks

The increasing ubiquity of mobile computing devices has made ad hoc networks everyday occurrences. In these highly dynamic environments, the multitude of devices provides a varied and rapidly changing environment in which applications must learn to operate. Successful end-user applications will not only learn to function in this environment but will take advantage of the variety of information available. Protocols for gathering an application’s contextual information must be built into the network to function in a timely and adaptive fashion. This paper presents a protocol for providing context information to such applications. We present an implementation and show how it provides context information to mobile applications in an on-demand manner. We also provide a simulation analysis of the tradeoffs between consistency and range of context definitions in highly dynamic ad hoc networks